For the purpose of reusing waste concrete and improving the properties of glass fiber reinforced cement(GRC), the effects of recycled waste concrete aggregate(RWCA)， fly ash and silica fume, which were either separately mixed or mixed together, on long term durability of GRC was researched using the methods of natural aging and accelerating ageing in 50℃ water. The results show that durability of GRC can be improved to some extent if natural sand of GRC is replaced by 30%(by mass, the same below) of RWCA, namely, the performance of GRC can be improved in terms of aggregate. If cement is replaced by 30% of fly ash, its addition is not favorable for the early flexural strength of GRC. If natural sand is replaced by 30% of RWCA, and at the same time, cement is replaced with 30% of fly ash, not only can the early flexural strength but aslo durability of GRC be improved. RWCA and fly ash can be mixed before adding or they can be added separately, the former is better than the latter. The early and late flexural strength of GRC can both be greatly improved if natural sand is replaced by 30% of RWCA, and at the same time the cement is replaced by 20% of fly ash and 10% of silicon fume, which is beneficial to the remaining of long term flexural strength of GRC. Analysis from micro methods(XRD, FTIR and SEM) shows that the three admixtures can all decrease the amount and size of Ca(OH)2 in the system. This can not only improve the flexural strength of GRC matrix, but also alleviate the erosion of glass fiber, which is favorable to improve the durability of GRC.